ARM: OMAP2+: AM43XX: Enable fixes for Cortex-A9 errata

This patch explicitly enables the fixes for the below errata applicable
for AM43x Socs as was done for OMAP4.

754322: Faulty MMU translations following ASID switch

775420: A data cache maintenance operation which aborts,
        followed by an ISB, without any DSB in-between,
        might lead to deadlock

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>